Method and apparatus for manufacturing slide fastener elements

ABSTRACT

This method and the apparatus for carrying out same are characterised essentially in that, during the weaving of the tape of the element, two separate filaments are inserted into the texture for constituting the fastening or coupling members propers by engaging by turns one and the other filaments between the warp yarns, at spaced intervals, to constitute at each point of insertion a transverse loop wound in one direction for one filament and in the opposite directions for the other filament, and meanwhile these filaments are disposed in the longitudinal direction on the side opposite to the coupling members proper, whereby these filaments constitute two variable-pitch helices of which the loops wound in opposite directions are imbricated, every other loop belonging to the same helix.

States Patent 1 y 9' i [111 3,871,420

Jakob Mar. 18, 1975 [541 fiigggiggggfiggfgi FOREIGN PATENTS ORAPPLICATIONS ELEMENTS l 945,3 l5 6/1969 Germany 24/205.16

[75] Inventor: Horst Jakob, Choisy-le-Roi, France Primary Examiner HemyJaudon [73] Assignee: Prestil, Choisy-le-Roi, France Attorney, Agent 22Filed: Jan. 2, 1974 [57] ABSTRACT [21] Appl. No.: 429,819

This method and the apparatus for carrying out same "f Apphcatmn a arecharacterised essentially in that, during the weavcommuatlon'm-part of295919- ing of the tape of the element, two separate filaments 1972'abandonedare inserted into the texture for constituting the fastenin orcou lin members to ers b en a in b' [30] Forelgn Apphcat'on Prmr'ty Dataturns one and the other filanFent s betu een th e v varp Oct. 13, 1971France 71.36698 yarns, atspaced intervals, to constitute at each pointof insertion a transverse loop wound in one direction 139/116, 139/118,139/384 B, for one filament and in the opposite directions for the24/205-13 C other filament, and meanwhile these filaments are dis- [51]Int. Cl D0311 35/00 posed in the longitudinal direction on the sideoppol Field of Search site to the coupling members proper, whereby these139/ 384 24/20513 205-16 C filaments constitute two variable-pitchhelices of which the loops wound in opposite directions are im-References Cited bricated, every other loop belonging to the same helix.

UNITED STATES PATENTS 6 Claims, 15 Drawing Figures 3189964 6/1965Galonska 24/205.l3 C

PATENTED MARI 81975 SHEET UlUF 10 PATENTED 1 8 I975 v 3,871,420 SHEETOZOF 1O PATENTEDHAR I 81% 3,871,420

SHEET 06 0F 10 PATENTED MAR 1 81975 SHEET 08 [1F 10 PATENTEDMR] 81975SHEET USUF 1O Fla/3.

METHOD AND APPARATUS FOR MANUFACTURING SLIDE F ASTENER ELEMENTS Thepresentapplication is a continuation-in-part application of Ser. No.295,019 filed Oct. 4, 1972 (now abandoned).

FIELD OF INVENTION The present invention relates to the manufacture ofslide fastener elements, namely the elements comprising a tape offlexible material carrying a row of cou pling members adapted to becoupled with another similar row by means of a control slide or tab.

DESCRIPTION OF THE PRIOR ART Various methods of manufacturing suchelements have already been proposed. According to one of these knownmethods the coupling members of a same rows are obtained by means of acontinuous filament by so shaping this filament as to form a series ofloops adapted to project from one edge of the corresponding supportingtape, the tape edges advantageously comprising thicker portions or otherdeformations adapted to facilitate the proper coupling with similarmembers carried by another identical element. To this end, the filamentemployed for making the coupling members may be caused to follow a coilor meander path.

In most instances these rows of coupling members thus obtained aremanufactured independently of the corresponding carrier tapes, andsubsequently secured thereto by suitable means, notably by sewing.

But according to a specific manufacturing method each row of couplingmembers is obtained during the very operation consisting in weaving thecorresponding tape, so that the filament utilized therefor is woven as aweft yarn with the warp yarn of this tape. This method is advantageousin that it eliminates the subsequent operation consisting in fixing. therows of coupling members to the corresponding carrier tapes.

However, the presence of this filament in the tape texture tends toproduce a certain tape distortion. This effect is due to the fact thatthe filament, having different physical properties in comparsion withthose of the textile yarns of the tape, comprises loops all wound in thesame direction.

SUMMARY OF THE INVENTION It is therefore the object of the presentinvention to provide a novel method of manufacture intended to eliminatethis drawback.

This method is characterised essentially in that, during the weaving ofthe tape of the element, two separate filaments are inserted into thetexture for constituting the fastening or coupling members propers byengaging by turns one and the other filaments between the warp yarns, atspaced intervals, to constitute at each point of insertion a transverseloop wound in one direction for one filament and in the oppositedirections for the other filament, and meanwhile these filaments aredisposed in the longitudinal direction on the side opposite to thecoupling members proper, whereby these filaments constitute twovariable-pitch helices of which the loops wound in opposite directionsare imbricated, every other loop belonging to the same helix.

The element thus obtained is advantageous in that it is prefectlysymmetrical and free of any tendency to twist up since both fastenerfilaments are wound in opposite directions. Moreover, the control tabcan be engaged indifferently in one or the other longitudinal directionon two sections of this element for obtaining a complete slide fastener.

The present invention is.also concerned with an apparatus for carryingout the method broadly disclosed hereinabove. This apparatus comprises aweaving loom arranged to provide laterally the space necessary for theoperation of two needles adaptedto introduce the two fastener filaments,said needles being disposed in close vicinity of the weft yarn weavingmember, across the movable sheet of warp yarns, whereas a retractablemember adapted to retain each loop formed by the two filaments registerswith one of the two edges of the sheet of warp yarns. On the other hand,adequate control means are provided for alternatively engaging one andthe other needles and insert the two filaments beyond the correspondingedge of the warp yarns, and retracting said needles to a fixed waitingposition, and meanwhile bringing the retaining member to its operativeposition and retracting same from this position.

Of course, this invention is also concerned with the slide fastenerelements obtained by carrying out the method of this invention,preferably by means of the apparatus broadly described hereinabove.

BRIEF DESCRIPTION OF THE DRAWINGS However, other specific features andadvantages of this inventionwill appear as the following descriptionproceeds with reference to the attached drawings given by way ofillustration and showing diagrammatically the coupling members with arelative spacing considerably greater than the spacing obtaining inactual practice, in order to facilitate the understanding of theinvention. In the drawings:

FIG. 1 is a diagrammatic plane view from above showing the manufactureof a fastener element according to this invention;

FIG. 2 is a cross-section taken along the line II-II of FIG. 1, showingthe members utilized for weaving the two fastener filaments;

FIG. 3 is a similar view showing the same members in different workingpositions;

FIG. 4 is a diagrammatic perspective view showing a fastener elementobtained according to the teachings of this invention;

FIG. 5 is a diagrammatic plane view from above of a slide fastenerconsisting of two elements manufactured according to the teachings ofthis invention;

FIG. 6 is a section taken along the line VI-VI of FIG. 5;

FIG. 7 is a plane view from above showing a modified form of embodimentof the method of this invention;

FIG. 8 is a diagrammatic perspective view of the fastener elementobtained by carrying out the modified method illustrated in FIG. 7,

FIG. 9 is a view similar to FIGS. 2 and 3 showing a modified form ofembodiment of the manufacturing method of this invention.

FIG. 10 is a perspective view of a loom for carrying out the method ofthis invention;

FIG. 11 is a part-sectional, part-elevational view of the devicecontrolling the needles for inserting the two filaments;

FIG. 12 is a diagram illustrating an ancillary device for tensioning oneof these filaments;

FIG. 15 is a part-sectional, part-elevational view showing the devicefor controlling the needle for inserting the two filaments in thismodified embodiment.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus employed forcarrying out the method of this invention comprises a weaving loomadapted to be operated for weaving this tape. Preferably, a needle loomis used, advantageously a single-needle loom capable of operating athigh production rates.

Thus, for instance, a needle loom such as the BONAS ES 1/D4 manufacturedby the British Company BONAS MACHINE COMPANY LIMITED of Sunderland(G.-B.). This loom, converted for operation according to the method ofthis invention, is illustrated in FIG. 10.

In this loom, the various warp yarns l constitute initially a sheettravelling in the direction of the arrow F past the needle 2 used forweaving the weft yarn 3. This yarn comprises simple loops disposed alongone of the edges 4 of the relevant tape 5. However, on the opposite edge6 a needle of known type, such as a latch needle 7, is provided forinterconnecting the various warp yarn loops, as illustrated in FIG. 1.

In the vicinity of the position occupied by the weft yarn needle 2 twomembers adapted to insert two filaments A and B are provided. Thus saidmembers are in the area where the warp yarns 1 are still divided intotwo separate sheets through the action of the loom heddles. The-twofilaments A and B are adapted to constitute the coupling members of thecorresponding fastener element. The members adapted to insert saidfilaments consist of a pair of needles 10 and 11, respectively, disposedon either side of the sheets formed by the warp yarns, in front of oneand the other face of these two sheets.

It may be noted more particularly that, due to their specificarrangement, these two are capable of forming, with one and the otherfilaments, loops wound in opposite directions, as will be described indetail presently.

These needles are of course movalbe and controlled by mechanical meansdesigned for alternatively engaging one and then the other needleinbetween the two sheets of warp yarns, beyond the edge 4 of the tape,then returning the needle backwards in order to form each time a loopwith the corresponding filament.

To this end, the present apparatus comprises likewise a retractableretaining member 12 adapted to retain in position the loop formed byeach filament as the corresponding needle 10 or 11 accomplishes itsreturn or backward stroke. However, this member is subsequentlyretracted for resuming its operative position when the next loop isabout to be made by means of the other filament of the fastener.

In the example illustrated, the two needles l0 and 11 are advantageouslyelbow, bent or curved needles and each of them is rotatably mountedabout a pivot pin 13 or 14 substantially parallel to the warp yarns.These needles are prefectly symmetric and as will be explained presentlytheir movements are also symmetric in relation to the median plane ofthe slide fastener.

Beyond their elbow, these needles l0 and 11 comprise each a groove 15formed on the side opposite to the relevant axis of rotation, thisgroove 15 leading to the hole 16 of each needle and adapted to receivethe relevant fastener filament A or B.

These two needles are controlled by cam means or any other suitablemechanism. The same applies to the loop retaining member 12 of the twofastener filaments.

FIG. 11 illustrates a typical embodiment of the device for controllingthe movements of the pair of needles 10 and 11. The rods 13 and 14carrying these needles are rotatably mounted in bearings'carried byasupport 45 secured to the frame structure 46 of the loom shown in FIG.10. Each rod 13, 14 carries a lateral arm 28 connected through a link 31to a control member 30 adapted to pull or push said link. The twocontrol member thus provided engage a pair of rotary cams 32 carried bya shaft 33. This shaft 33 is operatively connected to the end of one ofthe rotary shafts 47 of the loom.

Spring means, not shown, constantly urge the control members 30 inengagement with the corresponding cams. The cam contours are such thatwhen actuate these control members 30 in order to cause with the propertiming the rotation of one of the two needles 10 or 11 in one directionthen in the opposite direction, whereafter a similar action is exertedon the other needle, and so forth as will be explained in detailpresently.

FIG. 13 illustrates a typical embodiment of a device for controlling themovable member 12 adapted to retain the loops of the two fastenerfilaments. This member is carried by the cranked end of a rod 48slidably mounted in a guide member 49 secured to the top of the loom.

The opposite end of this rod is resiliently urged for engagement-with acontrol cam 50 rotatably driven from a shaft coupled to one of the powershafts of the loom. A spring 51 is provided to this end.

Now the cam contour is such that at the proper time the cam 50 causesthe retaining member 12 to be inserted into the loops formed by one ofthe fastener filaments A or B, whereafter this member 12 is retracted asanother loop is formed by the other filament, and so forth.

It is not compulsory to provide a specific device for feeding thefastener wires A and B. In fact, these may be simply pulled as necessaryby the fastener tape during the weaving operation, inasmuch as thefastener wires A and B are incorporated in said tape and the latter isdriven forwards in the loom.

However, in this case it is nevertheless necessary to provide a devicefor braking one or the other filaments or wires A and B and thustensioning them and properly shape the loops.

The arrangement is such that at predetermined time intervals the needle10 penetrates between the two sheets of warp yarns 1 for example at anintermediate point of the width thereof. To facilitate the penetrationof both needles at this specific point, the conventional cam meanscontrolling the heddles for separating the warp yarns of the two sheetsmay be modified, at least as far as some of these heddles are concerned.

In fact, this modification may involve only the warp yarns 1a locatedalong the selvedge of the tape and between which the fastener filamentsA and B are inserted.

The cams controlling the heddles associated with these warp yarns 1a arethan modified with a view to accentuate the separation of these yarns,as illustrated in FIGS. 2 and 3 and thus facilitate the engagement ofone of the needles or 11 between these yarns. On the other hand, thecams controlling the heddles of the other warp yarns [may be modifiedwith a view to reduce the relative spacing of these yarns at the samepoint and for the same'purpose, but it will readily occur to thoseconversant with the art that this lastmentioned modification .is quiteconventional in a weaving loom.

The insertion of the needle 10 takes place of course by means of arotational movement of said needle 10 as shown by the arrow F Saidneedle will thus cause thefilament A to form the first half 17 of theloop to be obtained at this position. When the needle 10 has reached itsoutermost position beyond the edge 4, th retaining member 12 is broughtto its operative position as shown in FIG. 2. Then, the needle 10 iscaused to recede due to its rotation in the direction of the arrow F soas to lay down locally the other half 18 of the loop to be formed atthis location During this operation, the retractable member 12 retainsin position the loop thus formed, so that it cannot be pulled backwardsduring the return movement of the needle 10 to its inoperative position.However, this retaining member is also adapted to permit a distortion ofthe filament section in order to constitute a coupling member 19 of thefastener during the same manufacturing process.

In fact, the traction exerted on the filament in the backward directioncauses this filament to be elongated against the retaining member 12.Now this elongation is attended by a modification in the cross-sectionalshape of the filament and therefore by the development of two lateralprojections therein. as illustrated in FIG. 1. Thus, a coupling memberis obtained which is adapted to catch identical members formed along theother fastener element during the actual use or imbrication of thefastener elements.

FIG; 12 illustrates a typical embodiment of a device suitable fortensioning each fastener filament A or B, and for tensioning same at theend of each loop.

This device comprises a holding clamp consisting of a movable jaw 34registering with a fixed jaw 35, on either side of the passage of thecorresponding wire 8. The movable jaw 34 is carried by the rod 36 of acontrol cylinder 37.

Downstream of this clamp, i.e., on the side located in the direction ofthe point of insertion of the wire 8 into the tape during the weavingoperation, a movable member adapted to tighten the wire loop formeddownstream is provided. This member consists of a roller 38 carried by arod 39 of a control cylinder 40. This roller 38 registers with the wireA or B and can thus push the latter back and cause same to form a loop41 between the pair of fixed rollers 42.

As a consequence of the formation of this loop, the wire A or B ispushed backwards so as to absorb any slack therein while tensioning theloop formed by this wire.

Of course, the jaw 34 must be in its clamping position during thisphase.

The operations of cylinders 37 and 40 is controlled by suitable means insynchronism with the other component elements of the machine.

The elongation of each filament A and B on said retaining member 12 mayif desired be completed by the application of heat to well-definedsports, in order to facilitate the formation of these coupling members19. the fastener elements consisting advantageously of thermoplasticmaterial. This local heating action may be produced by using jets orheated air or an inert hot gas, such as nitrogen, or any other suitableand known means. Thus, the retractable retaining member may be connectedto a suitable generator of supersonic waves capable of heating thefilament.

When the first looping needle 10 has been withdrawn, it remainsstationary in its inoperative position as shown in FIG. 3. But in thisposition it permits the free winding off of filament A in the directionof the warp yarns, as these yarn continue their forward or feedmovement. Thus, a connecting portion 20 between two successivetransverse loops can be completed.

However, during this time, the needle 2 of the weaving loom makes one orseveral picks with the weft yarn.

Then, the second looping needle 11, which remained stationary during theabove-described operation, becomes operative in turn by introducing theother filament B into the gap between the two sheets of warp yarns. Themode of operation of this needle is then the same as that of the firstlooping needle 10, with the difference however that the winding of theloops formed with this filament B takes place in the reverse directionin comparison with the winding of the loops formed with filament A. Thisis due to the fact that the two needles 10 and 11, having the sameshape, are disposed in opposition to each other on either side of thesheet of warp yarns.

Thus, during its operative stroke (in the direction of the arrow F.,)the second needle 11 will lay down the first side or portion 21 of theloop to be formed at this location by filament B. But it should be notedthat this loop side is then located at the bottom, considering theplanes of FIGS. 2 and 3, whereas the first side 17 of the loops formedwith filament A were placed at the top.

When this needle 11 has attained its endmost position illustrated inFIG. 3, the retaining member 12 resumes its operative positionpreviously abandoned after the return stroke of the first looping needle10 towards its inoperative position. Then the second needle 11 resumesby itself its inoperative position by rotating in the direction of thearrow F so as to lay down the second side 22 of the loop. But, at thesame time, a coupling member 19 is formed on the projecting end of thisloop, as described hereinabove in connection with the mode of operationof the first needle 10.

The second looping needle 11 then remains station ary in its inoperativeposition illustrated in FIG. 2, while permitting the free winding off offilament B in order to form a connecting portion 23 between the twotransverse and successive loops formed with said fila ment B.

During this period, the needle 2 of weft yarn 3 makes one or severalpicks, and subsequently the first looping needle 10 resumes itsoperative position for making another loop with filament A, and soforth.

Thus, transverse loops are formed alternatively with one and the otherfilaments A, B, by winding these filathe tape, in relation to the medianplane of the fastener element.

In this respect, it may be noted that the two filaments A and B are notwoven with the warp and weft yarns of the tape, as observed in certainknown prior art manufacturing processes. In fact, these filaments aresimply inserted in between the warp and weft yarns. Moveover, thesefilaments comprise both transverse portions, namely the transverseloops, and longitudinal portions, namely the connecting portions orsections or 23.

Due to the particular method of distributing the filaments A and B, eachfilament forms along the tape selvedge or marginal portion avariable-pitch coil constituting a series of loops disposed intransverse planes and connecting elements 20, 23 extending in thelongitudinal direction But, as already explained in the foregoing, thetransverse loops of these two coils are wound in opposite directions.

One of the essential advantages deriving from the method of thisinvention lies in the fact that the winding of the loops formed with thetwo filaments in opposite directions affords a positive balance betweenthe possible tendency to twist up, which might develop as a consequenceof the winding of these filaments between the warp yarns and the weftyarns of the tape.

Another advantageous features is that the elements thus obtained isperfectly symmetrical. Thus, it is possible to cut out two sections ofthis element and assemble these sections with each other after turningthem in opposite end to end relationship. Besides, FIGS. 5 and 6illustrate a complete slide fastener thus obtained by assembling twosections of a same fastener element manufacturing according to theteachings of this invention.

Another advantageous feature consists in that the control tabs can beset in position in one or the other direction, indifferently. This isalso due to the perfect symmetry of the fastener elements obtained bycarrying out the method of this invention. Now, this easy tab fittingpossibility constitutes an important advantage notably in themanufacture of certain ready-made garments. Another advantageous featurecharacterising this invention relates to the improved tab guiding actionafforded by its method. In fact, by virtue of the symmetry of theelement section thus obtained two identical projecting beads are formedon one and the other face of this section. Thus, these beads act asguide rails for the slide or tab on one and the other face of theelement. Now in most hitherto known slide fasteners types only one ofthe two faces comprises such projecting guide bead.

Another reason of the improved tab guiding action obtained with thepresent invention is due to the fact that on both faces of the slidefastener element the connecting portions between the transverse loopsformed by the aforesaid filaments A and B are somewhat offset. In fact,when on one of the tape faces a connecting portion leads to a transverseloop, thus breaking the continuity of the tab guiding slideway, thenecessary guiding action is continuous on the other faceof the 8 tape,due to the presence of the corresponding filament.

Of course, the manufacturing method of this invention should not beconstrued as being strictly limited to the steps described hereinabovewith references to the apparatus illustrated in FIGS. 1 to 3 of thedrawings. Thus, FIGS. 7 and 8 illustrate a modified form of embodimentof this method which is intended for improving the holding in positionof the transverse loops formed by the two fastener filaments. Thisresultis obtained by properly anchoring each loop at the base, i.e..where each loop merges into the corresponding connecting portions 20 or23.

This anchoring action is produced by means of another loop 24 formed bymeans of the weft yarn 3 at this location. This is obtained by causingthe premature return of the weft yarn on itself before attaining thecorresponding edge 4 of the tape, at the location of each transverseloop of the two filaments A and B of the corresponding fastener element.

The premature return of the weft yarn 3 at 24 to the bottom of the turnsformed by the fastener wire is obtained by modifying the manner in whichthe warp yarns la provided along the selvedge are lifted.'ln fact, it isonly necessary that all the selvedge warp yarns la be lowered at thelocation corresponding to the time of the positive stroke of needle 2 sothat the weft yarn 3 can pass above these warp yarns and then, duringthe return stroke, this yarn 3 will not find any obstacle beforeattaining the very base of the fastener wire, so that it will form aloop 24 only at this point.

As a matter of fact, this technique is well known and conventional inthe art of passementry, when patterns are formed on only one portion ofthe tape width.

With this modification in relation to the other warp yarns 1b (whichtakes place only at the proper time) the weft yarn 3a will form a loop24 at the root of each transverse loop of the two fastener filaments asillus trated in'FIGS. 7 and 8. Thus, the loops formed by means of thefastener filament are safely anchored while avoiding notably anypossibility of untimely slippage thereof in the transverse direction.

Instead of disposing the needles for introducing the two filaments A andB on either side of the movable sheet for warp yarns 1, it would also bepossible to dispose said needles in front of a same face of this sheet,provided that said needles are off-set to each other in the longitudinaldirection. In this case it would be necessary of course to provideunequal time intervals between the moments whereat said needles arerendered operative.

On the other hand, in this case it would be necessary to use two needles10a and 11a (see FIG. 9) of different types, capable of producing thewinding in opposite directions of the loops formed with one and theother filaments; in this case, one needle, for example needle 11a, maybe-identical with the above-described needles 10 or 11 of the precedingexample, and comprise a groove 15 on the side opposed to its pivot axis.As to the other needle 10a, it would then comprise a groove but on theopposite side, i.e., towards the pivot 14, in order to permit thewinding the loops in the other direction with respect to the windingdirectionof needle 11a.

Of course, many other modifications may be contemplated in connectionnot only with the various steps of the manufacturing method of thisinvention but also with the component elements of the apparatus employedfor carrying out this method, and with the fastener elements themselves.

Possibly, the two sides of each loop formed by means of the fastenerfilaments may have a different relative position in lieu of the directsuperposition contemplated in the above-described examples.

The coupling members could also be manufactured differently. Thus,instead of forming these members by pulling the retaining member 12, itwould be possible to provide preliminary distortions on the fastenerelements at properly spaced locations so that these distortions lie onthe end of the projecting loops formed by these filaments during theirinsertion in the course of the tape weaving operation.

But, conversely, it would also be possible to form these couplingmembers after making the loops of the two fastener filaments andinserting these filaments throught the tape.

Besides, the two fastener filament inserting looping needlescontemplated in the examples illustrated could be replaced byrectilinear needles performing simple reciprocating movements, or by anyother suitable members capable of positioning the two fastenerfilaments.

FIGS. 14 and 15 illustrate this modified embodiment. As clearly shown,in this modified embodiment two separate rectilinear insertion needles10b and 11b are used; a reciprocating motion is imparted thereto alongtwo oblique axes, instead of a pivotal motion as in the case of thecurved needles l and 11.

Both rectilinear needles b and 11b are disposed in a same planeperpendicular to the general plane Z-Z of the tape being woven on theloom contemplated therefor. These needles are secured to a pair ofmovable supports 25a and 25b slidably mounted ina pair of stationarytubular guide members 26 rigid with .a bracket 27 secured to the loomframe structure.

These movable supports 25a and 25b for the aforesaid pair of needles aredriven through a pair of bent levers 28a, 28b fulcrumed to a pair offixed pivot pins 29 and driven in turn from push-rods 30a and 30bconnected through links 31 to said levers.

These push-rods register with a pair of rotary control cams 32a and 32bcarried by a rotary shaft 33 adapted to be coupled to one of the rotaryshafts of the loom.

The contour of these cams 32a, 32b is such that they control by turnsthe movement of needle 10b in the direction of the arrow F so as toinsert the corresponding wire into the tape, whereafter this needle iswithdrawn and the other needle 11b is moved in the direction of thearrow F to insert the wire carried by this needle into the tape, andfinally returning the needle backwards, and so forth.

Of course, these movements are synchronized with those of the retainingmember 12 provided along the tape selvedges so as to retain each loopthus formed by means of one and the other of said pair of wires orfilaments.

As far as the apparatus employed for carrying out the method of thisinvention, it may be noted that different types of weaving looms may beused. However, in the case of a needle-type weaving loom, it would bepreferable to use a loom type providing the room necessary for mountingthe pair of additional needles intended for introducing the fastenerfilaments, and also for positioning the retaining member 12 and thevarious correspending mechanical control means. However, a conventionalloom could also be used, notably a loom comprisingone or a plurality ofshuttles, for introducing the weft yarn.

What I claim is:

1. Method of manufacturing a slide fastener by incorporating acontinuous filament between the warp and weft yarns of a tape, in orderto form with said filament transverse loops constituting couplingmembers along one edge of said tape, this method being characterised inthat during the tape weaving operation there are inserted into said tapetwo separate filaments adapted to form the coupling members by engagingby turns said filaments between said warp yarns at spaced intervals, inorder to form at each point of insertion a transverse loop formed bywinding said filaments in opposite directions, by turns, while disposingsaid filaments in the longitudinal direction on the side opposite to thecoupling members proper, whereby said filament form two variable-pitchhelices of which the loops wound in opposite directions are imbricated,every other loop belonging to the same helix.

2. Method of manufacturing a slide fastener according to claim 1,characterised in that during the formation of each loop with one or theother filament a retaining member is brought to the tape edge lying onthe side of said coupling members, and introduced into the previouslyformed loop, whereby said retaining member, during its return stroke,can elongate said loop and cause in a manner known per se a distortionof the cross-sectional shape of the filament, this distorted portionconstituting a coupling member perse, whereafter said retaining memberis retracted until the next loop is formed with the other filament.

3. Manufacturing method according to claim 2, characterised in thatduring the formation of the transverse loops with one and the otherfastener filaments said filaments are wound on themselves in order tocause the connecting portions between two loops of a same filaments toconstantly project from a same face of the fastener element, thecorresponding connecting portions of the other filament projecting fromthe other face of said fastener element.

4. Apparatus for manufacturing a slide fastener by incorporating twocontinuous filaments between the warp and weft yarns of a tape, saidapparatus comprising a weaving loom capable of weaving a tape, and twoneedles for introducing the two fastener filaments, said last-namedneedles being disposed in the vicinity of the weft yarn weaving member,and registering with the movable sheet of warp yarns, a retractableretaining member adapted to engage each loop formed by the two filamentsbeing provided along one of the edges of the sheet of warp yarns,adequate control means being provided for alternatively causing one andthen the other needles to insert the two filaments beyond the relevantedge of the warp yarns and then move back to a fixed waiting position,and at the same time to bring said retaining member to its operativeposition and subsequently move said member back to its retractedposition.

5.An apparatus for manufacturing slide fasteners according to claim 4,characterised in that the needles provided for introducing the twofastener filaments are of the elbow type and pivotally mounted about apair of fixed axes, said needles being disposed on either side of thesheet formed by said warp yarns.

6. Apparatus according to claim 4, characterised in that the needlesprovided for introducing the two filaments are straight and driven forrectilinear reciprocating action.

1. Method of manufacturing a slide fastener by incorporating acontinuous filament between the warp and weft yarns of a tape, in orderto form with said filament transverse loops constituting couplingmembers along one edge of said tape, this method being characterised inthat during the tape weaving operation there are inserted into said tapeTwo separate filaments adapted to form the coupling members by engagingby turns said filaments between said warp yarns at spaced intervals, inorder to form at each point of insertion a transverse loop formed bywinding said filaments in opposite directions, by turns, while disposingsaid filaments in the longitudinal direction on the side opposite to thecoupling members proper, whereby said filament form two variable-pitchhelices of which the loops wound in opposite directions are imbricated,every other loop belonging to the same helix.
 2. Method of manufacturinga slide fastener according to claim 1, characterised in that during theformation of each loop with one or the other filament a retaining memberis brought to the tape edge lying on the side of said coupling members,and introduced into the previously formed loop, whereby said retainingmember, during its return stroke, can elongate said loop and cause in amanner known per se a distortion of the cross-sectional shape of thefilament, this distorted portion constituting a coupling member per se,whereafter said retaining member is retracted until the next loop isformed with the other filament.
 3. Manufacturing method according toclaim 2, characterised in that during the formation of the transverseloops with one and the other fastener filaments said filaments are woundon themselves in order to cause the connecting portions between twoloops of a same filaments to constantly project from a same face of thefastener element, the corresponding connecting portions of the otherfilament projecting from the other face of said fastener element. 4.Apparatus for manufacturing a slide fastener by incorporating twocontinuous filaments between the warp and weft yarns of a tape, saidapparatus comprising a weaving loom capable of weaving a tape, and twoneedles for introducing the two fastener filaments, said last-namedneedles being disposed in the vicinity of the weft yarn weaving member,and registering with the movable sheet of warp yarns, a retractableretaining member adapted to engage each loop formed by the two filamentsbeing provided along one of the edges of the sheet of warp yarns,adequate control means being provided for alternatively causing one andthen the other needles to insert the two filaments beyond the relevantedge of the warp yarns and then move back to a fixed waiting position,and at the same time to bring said retaining member to its operativeposition and subsequently move said member back to its retractedposition.
 5. An apparatus for manufacturing slide fasteners according toclaim 4, characterised in that the needles provided for introducing thetwo fastener filaments are of the elbow type and pivotally mounted abouta pair of fixed axes, said needles being disposed on either side of thesheet formed by said warp yarns.
 6. Apparatus according to claim 4,characterised in that the needles provided for introducing the twofilaments are straight and driven for rectilinear reciprocating action.